The linen bag is better. My reasons are: you don't want your bread in an airtight wrap, as this will cause moisture to soften the crust and create the atmosphere that mold thrives in; you can reheat your bread in the linen bag with your oven on low but not recommended for the wax paper; also, if you are unfortunate enough to have bread start to mold, you'll appreciate the ability to wash that linen bag in super hot water. A paper bag, brown or otherwise, has the same breath-ability as the linen bag, but you can't wash it either.